Some do, some don't. Native ancestry is more well accepted than any SSA ancestry. Those who are black deal very well with this and are very proud of being black, the problems goes with those who are pred. white but also show some SSA or Native traits.. many of them like to be related only with their white ancestry. Go tell some light skinned Brazilian about a possible SSA admixture, specially those who are Upper or Middle Class and you will see their reaction..